Differential Diagnosis for Patient with Boils

The patient presents with multiple boils on her right labial majora and one on her right buttock, with a history of MRSA. Here's a differential diagnosis organized into categories:

• Single Most Likely Diagnosis

  • MRSA Infection: Given the patient's history of MRSA and the presence of boils, which are a common manifestation of MRSA skin infections, this is the most likely diagnosis. MRSA can cause recurrent skin infections, and the locations of the boils are consistent with areas prone to MRSA infections.

• Other Likely Diagnoses

  • Folliculitis: This is an inflammation of the hair follicles, which can be caused by bacterial infections, including MRSA. The presence of boils on the labial majora and buttock could be consistent with folliculitis, especially if the areas are prone to friction or shaving.
  • Furunculosis: This condition involves the recurrence of furuncles (boils) and can be associated with MRSA. The patient's history and presentation could suggest a diagnosis of furunculosis, particularly if the boils are recurrent.
  • Cellulitis: Although less likely given the localized nature of the boils, cellulitis is a bacterial skin infection that could present with similar symptoms. However, cellulitis typically involves more diffuse areas of redness and swelling.

• Do Not Miss Diagnoses

  • Necrotizing Fasciitis: Although rare, this is a life-threatening condition that requires immediate attention. It involves a rapidly spreading infection of the fascia, which could initially present with symptoms similar to those of a boil or cellulitis. The presence of severe pain, fever, and rapid progression of symptoms would raise suspicion for this diagnosis.
  • Ecthyma Gangrenosum: This is a rare but serious condition associated with Pseudomonas aeruginosa infection, which can present with skin lesions resembling boils. It is more common in immunocompromised patients and would be a concern if the patient has a weakened immune system.

• Rare Diagnoses

  • Hydradenitis Suppurativa: This chronic skin condition involves recurrent, painful abscesses and nodules, typically in apocrine-gland-bearing areas such as the groin and buttocks. While it could explain the patient's symptoms, the presence of a clear history of MRSA and the specific locations of the boils make this a less likely diagnosis.
  • Cutaneous Anthrax: This rare condition, caused by Bacillus anthracis, can present with a skin lesion that evolves into a painless ulcer with a characteristic black eschar. Although extremely unlikely without specific exposure history, it is a rare diagnosis to consider in the differential of skin lesions.